Chain hammer mill



July 17, 1962 w. J. SACKETT 3,0

CHAIN HAMMER MILL Filed Aug. 21, 1958 7 Sheets-Sheet 1 IIIIIIIIIIIIIIIIII'IIIIM ATTORNE July 17, 1962 Filed Aug. 21, 1958 w. J. SACKETT 3,044,718

CHAIN HAMMER MILL 7 Sheets-Sheet 2 INVENTOR war/fer L/. 4522 aka 77 July 17, 1962 Filed Aug. 21, 1958 W. J. SACKETT CHAIN HAMMER MILL 7 Sheets-Sheet 3 INVENTOR wa/fe'r 5acA'e/"fi ATTORNEY July 17, 1962 w. J. SACKETT CHAIN HAMMER MILL 7 Sheets-Sheet 4 Filed Aug. 21', 1958 INVENTOR Ufa/7 cf. sac/rs?" 7".

ATTORNEY July 17, 1962 w. J. SACKETT 3,044,718

CHAIN HAMMER MILL Filed Aug. 21, 1958 '7 Sheets-Sheet 5 was/fer (f, Sac/1:277

ATTORNE July 17, 1962 w. J. QSACKETT 3,044,718

CHAIN HAMMER MILL Filed Aug. 2l, 1958 7 Sheets-Sheet 7 l FE'. D3

I NVENTOR BY A%N{ United States Patent Ofifice 3,044,718 Patented July 17., 19,62

3,044,718 CHAIN HAMMER MILL Walter J. Sackett, Baltimore, Md., assignor to The A. J.

Sackett 8: Sons Company, Baltimore, Md., a corporation of Maryland Filed Aug. 21, 1958, Ser. No. 756,444 6 Claims. (Cl. 241-189) This invention relates to a mill for cracking or breaking up rock formations such as phosphate rock which is used extensively in the making of fertilizers.

One of the objects of the invention is to make a mill which will be very inexpensive in the initial construction and in which the wear portions cannot only be cleaned readily, but replaced or repositioned to present new wear surfaces to continue the life of the mill substantially indefinitely.

Another object of the invention is to make a mill which is simple in construction and assembly and yet very rugged so that it will undergo long use without attention or repairs or adjustment.

Another object of the invention is to break large particles of material and to produce in that breakage as few fines or finely broken material as possible.

Another object of the invention is to so mount the hammers that they and their supports will not be injured should excessively large pieces of material pass to the mill.

Another object of the invention is to construct a mill,

which will remain operative when working on material which tends, in part, to cake and clog the mill.

An object of one modification of the invention is to utilize a grid surface constructed of an integral piece of a material which is readily available on the market when replacements are required.

An object of another modification of the invention is to construct the grid of bars which may be removed as a group without initially cracking any of the accumulated rock dust from its adherence on the bars; at times this dust solidifies with atmospheric moisture so that it is very ditlicult to remove.

Another object is to so support the bar ends, when bars are used so as to grid, as to place a minimum of strain on certain of the parts used to connect the bars with the mill casing.

Other objects and advantages of the invention will be apparent from the following description and the accompanying drawings forming a part hereof and in which:

FIGURE 1 is a transverse sectional view substantially through the center of the mill.

FIGURE 2 is a sectional view on line 2-2 of FIG- URE 1.

FIGURE 3 is a sectional view on line 33 of FIG- URE 1.

FIGURE 4 is a sectional view on line 44 of FIG- URE 1.

FIGURE 5 is a fragmentary elevational view of a portion of expanded metal forming the grid of one modification.

FIGURE 6 is a sectional view on line 66 of FIG- URE 5.

FIGURE 7 is a sectional view through one of the hammers of the mill and of its accompanying supports.

FIGURE 8 is a fragmentary sectional view showing the mounting of the hammers on their supporting rods.

FIGURE 9 is a fragmentary sectional view of a modification showing a bar formation for the grid.

FIGURE 10 is a sectional view of the bar supports and hammers on line 10-10 of FIGURE 9.

FIGURE 11 is a contracted sectional view of the bar supports on line 11-11 of FIGURE 9.

' in a line with the link bight.

FIGURE 12 is a fragmentary elevational view of a modification of the grid bar member support.

FIGURE 13 is a fragmentary partial elevational and partial sectional view of the grid bar members and the supports shown in FIGURE 12 in their assembled position.

FIGURE 14 is a sectional view on line 1414 of FIG- URE 13.

FIGURE 15 is a partial transverse sectional view showing a modification of the curtain, on line 15-15 of FIGURE 16.

FIGURE 16 is a sectional view on line 1616 of FIG- URE 15.

In the drawings similar numerals refer to similar parts throughout the several views.

The rotary shaft 1 is mounted in bearings 2 and. rotated by a belt 3 on pulley 4. The casing for the mill is made up of three sections, a lower section 5, an upper quarter section 6 and a forward quarter section 7. The sections have flanges 8 extending outwardly thereon to connect the sections together by bolt 9. The upper section have a cover 10 bolted to them by bolts 11 and the rear cover section has a chute 12 bolted, to it through which the material passes to the mill. The quarter sections 6 or 7 can either be removed for Working on the interior of r the mill for cleaning or replacement of parts. Hand holes 13 are placed in the upper forward quarter section 7 and ther forward portion of the lower section 5, the covers 14 of which may be removed for similar cleaning or replacement operations of less extent than one requiring removal of a quarter section. Hopper wall 15 is in the forward upper section of the mill housingand; is welded to the opposite sides 16 of this section. A similar wall of greater vertical extent 17 is welded to the sides of the rear quarter sections of the housing and this wall has a horizontally extending flange 18 with openings between fiange portions 18 to permit the passing of fine materials which may have passed through openings 19 in hopper section 17, and hopper section 15 has similar openings 20 therein through which fine material passes down between the sides of the housing and the grid structure 21 shown in FIGURES 1, 2, 3, 5 and 6, made of expanded metal.

The rotor or driven shaft 1 has spaced thereon by spacing rings 22 a plurality of plates 23 which are of rectangular formation and have holes passing through their centers for the shaft. Plates 23 are alternately placed at right angles to each other and the ends of each group of plates have center openings therein through which pass rods 24. These rods 24 have between adjacently-extended ends of the plates circular segment bearing blocks 25 with an inner circumference like that of rods 24 and they are free to rotate on the rods. These bearing blocks 25 are cut out as shown in FIGURES 7 and 8 at 26 to permit one end of a chain link 27 to lie therein and the link is welded thereto as shown at 28. The link next to that welded on block 25 may pass between adjacent plates 23, as shown in FIGURE 1 and that link is guided by the plates 23 to aid in maintaining the chain normal tov shaft 1, since the ends of the links expand nearly to full width Each chain has four links as shown in FIGURES 1 and 2. .The link 29 at the other end of the chain is permanently attached to a hammer 30, which is a rectangular block 31 with openings 32 and 33 in the end and side wall thereof respectively, through which openings the block is welded to link 29 as shown at 34. Steel is also deposited as an outer casing 35 on the blocks to give the. hammers a longlife. The rods 24 are fastened in the plates 23 by means of nuts 36 held from turning by cotter pins 37. As has been shown especially in FIGURE 2, the hammers of each alternate row are staggered from those of the adjacent row so that a following group of hammers will follow the spacings between the hammers of the preceding group.

Welded to the underside of cover 10 are bars 38 extending transversely of the mill, other bars 39 at right angles thereto extending parallel to rotor axis, the two sets of bars forming an egg-crate-like structure with a rod 40 passing across the mill, parallel to bars 39 and supported in openings in bars 38. This rod is held in place by cotter pins 41 passing through the ends thereof and it has thereon five depending chains 42 fitting around sleeves 43 on the rod and spaced between bars 38 by spacers 44. Each of these chains has three links depending down toward the periphery of the rotor hammers.

At the rear of this set of bars 38 and 39 is another group of bars 45 and 46, bars 46 extending parallel to rod 40. Bars 46 have drilled openings with bolts 47 passing therethrough and held by nuts and cotter pins 43. There are four of these bolts placed in staggered position between the chains mounted on rod 40. These bolts likewise have sleeves 49 thereon for receiving therearound links of depending chains 56 of which there are four with two links each and they are spaced between the bars 46 by spacers 51.

These depending chains form a chain curtain in close proximity to the rotating hammers and the hammers throw the material against the chains to give the material an initial breaking before it is crushed or cracked on grid 21.

The grid 21 is made of expanded metal and the metal is first slit and then stretched and bent as shown in FIG- URE forming a series of half loops, and then another alternate group of slits is made and the metal further stretched and bent. This forms sections 52 of metal with a rectangular cross-section as shown at 53 with an outer edge projecting toward the oncoming hammers. The expanded metal is welded to a framework 54 which is in turn bolted to a further framework 55 welded at its sides to the sides of the mill housing. As seen in FIGURE 1 the expanded metal sections are two, one in the lower section of the housing and one in the upper forward quarter section of the housing. The sections of the expanded metal may be removed for replacing and they may be cleaned by the removal of the hand-hole covers 14.

A modification of the grid structure is shown in FIG- URES 9 to 14 inclusive in which bar members 56 extend concentric to and cross-wise.of the mill parallel to the rotor axis, which are likewise placed with a corner of the edges of the bars toward the hammers. The bars fit shaped openings in one side plate 16 of the housing and are held in those openings by cotter pins 57. The other side of the housing 16 has an arcuate slot 58 cut therein and an arc-shaped member 59 with bar-shaped openings therein and with wings 60 extending from each side thereof is bolted as at 61 to side walls 16 of the housing. The wing members 60 rest on the flange 62 projecting from the sides of the housing and the bottom of the arcshaped member 59 rests on flange 63 projecting from the bottom of the mill housing. These actual resting places for the arc-shaped member take the strain from the bolts 61 attaching the member to the side wall of housing. Also a bearing for the arc-shaped member 59 is the ends 64 of the central flanges 62. Bars 56 are held in the arcshaped member 59 both by cotter pins 65 and set screws 66. Upon the removal of the bolts 61 and cotter pins 57, because the ends of the bars are clean, the bars may be removed as a group by removing the arc-shaped member 59 through the opening 58 for cleaning or turning around in their mounting or replacing.

Rather than have a heavy arc-shaped member 59, a plate member 67 can be used in which the bars 59 are held simply by cotter pins as shown at 68. These plates 67 are likewise held on the side wall of the housing by bolts 69 and here again the group of bars can be removed together. This plate member 67 likewise has wings 70 to bear upon center flanges 62 and the lower end bears upon lower flanges 63.

A modification of the chain curtain shown in FIG- URES 3 and 4 is shown in FIGURES l5 and 16 in which the curtain 71 is made of expanded metal, like that of the grid 21; in this modification, the curtain 71 is welded to a tube 72 pivoting on rod 73, mounted between brackets 74 welded on hinged cover 75, hinged at 76 to the member 77. Hinged cover 75 has a handle 78 by which to raise it, and it is held down by bolts 79 at its edges and screws 80 at its free end. A stop plate 81 having angle reinforcing inserts 82 is also welded to the hinged cover 75, to limit the forward swing of the curtain. The curtain extends adjacent the peripheral line of throw of hammers 3i) and receives and breaks the material thrown by the hammers 30. Cover 83, the opening 84 in which is closed by hinged cover 75, and member 77, to which hinges 76 are welded, are held by bolts 85 to the front wall of the mill.

It will thus be seen that an economical and rugged mill is constructed according to this invention which may be readily repaired and the two formations of the grid can likewise be very economically replaced or repaired. The phosphate rock for which the mill is primarily designed tends to stick and harden to such a degree that the grid must be kept clean and the form of the mounting for the hammers prevents any accumulation of material on them would interfere with their effective operation.

It will be appreciated that many changes may be made in the mill illustrated without departing from the invention.

What is claimed a new and is desired to be secured by Letters Patent is:

1. In a breaking mill having a rotor on a transversely extending shaft and carrying swinging hammer elements in a casing with an arcuate grid substantially concentric with and in proximity to the peripheral swing of the hammers on the forward downward side of their swing and the casing having an upper inlet to the side adjacent the upper swing of the hammers and a layer unobstructed discharge opening spaced laterally from the grid, comprising in combination a plurality of substantially rectangular plates having openings centrally thereof threaded on the rotor shaft normal thereto and each alternate plate having its ends projecting normal from the side of the adjacent plate, spacers on the rotor shaft between each plate of an outer diameter substantially the width of the plates, the plate projecting ends having openings therethrough and rods therein, parallel to the rotor shaft, each rod having a chain thereover of a plurality of links each of right angles to its adjacent link between pairs of the projecting ends of alternate plates, the total width of two spacers and the thickness of an intermediate plate exceeding the width of the chain links with small clearance to receive between the plates the rod connected and directly adjacent links, means bearing on the rods and receiving thereover the inner link of the chain to space the chain links on the rods substantially centrally between adjacent plates and a hammer at the outer end of each chain, said hammers being fiat of face and violently throwing the incoming material against the grid, the hammers on each rod being slightly spaced from each other and the hammers on adjacent rods parallel with the rotor shaft longitudinally alternating, to cover the entire grid surface, the plural linked chains collapsing upon the encounter by the hammers with excessively large particles of material and being separately guided by the projecting ends of the plates between which they are mounted.

2. The mill of claim 1 in which the chain link spacing means comprise circularly segmented bearing blocks substantially the length of the space between adjacent projecting plate ends bearing on the rods and having the chain link end therearound afiixed thereto centrally longitudinally of the block.

3. The mill of claim 1 in which the casing inlet comprises a hopper having a cover and a chute on the rear of the cover, on the rotor side of the mill adjacent the upper approach of the hammers and a plurality of chains depending from the forward under side of the hopper cover to adjacent the peripheral swing of the hammers, the chains being spaced in a row parallel to the rotor shaft to engage the material thrown by the hammers prior to its entry between the hammers and grid.

4. The mill of claim 1 in which the grid comprises a plurality of circularly spaced angularly directed members of rectangular cross-section parallel to the rotor shaft mounted in the mill casing, an angular edge of each rectangular member being inwardly axially directed to engage the material thrown by the hammers and spaced a constant distance from the distal ends of the hammers of the rotor, at one side adjacent the grid end the casing having an arcuate slot therein and an arcuate plate removably aflixed to the outside of the casing and covering the slot, the plate having openings therein to receive thereinto and support one end of the members, said members being removable from the casing in a group through the slot upon removing the plate.

5. The mill of claim 1 in which the grid comprises a plurality of circularly spaced angularly directed members of rectangular cross-section parallel to the rotor shaft mounted in the mill casing, an angular edge of each rectangular member being inwardly axially directed to engage the material thrown by the hammers and spaced a constant distance from the distal ends of the hammers of the rotor, at one side adjacent the grid end the casing having an arcuate slot therein and an arcuate plate removably affixed to the outside of the casing and covering the slot, the plate having openings therein to receive thereinto and support the ends of the members, the casing having an outwardly projecting horizontal flange centrally of the plate and the plate having wings thereon, bearing on said flange, to support the plate on the flanges, said members being removable from the casing in a group through the slot upon removing the plate.

upper approach of the hammers and a curtain mounted on and depending from the forward under side of, the hopper cover to adjacent and above the peripheral swing of the hammers to swing parallel to the mill rotor shaft to receive the first impact of material thrown by the hammers thereagainst.

References Cited in the file of this patent UNITED STATES PATENTS 129,359 Moore July 16, 1872 991,477 Buchanan May 9, 1911 1,076,128 Quenner Oct. 21, 1913 1,280,838 Rapp Oct. 8, 1918 1,433,042 Sedberry Oct. 24, 1922 1,457,210 Crane May 29, 1923 1,713,507 Ammon May 21, 1929 1,752,290 Ammon Apr. 11, 1930 1,839,532 Calhoun Jan. 5, 1932 1,872,233 Borton Aug. 16, 1932 1,889,129 Nielsen Nov. 29, 1932 2,095,385 Heisserman Oct. 12, 1937 2,200,374 Poese May 14, 1940 2,384,531 Bryant Sept. 11, 1945 2,411,302 Stine Nov. 19, 1946 2,424,316 Johnston July 22, 1947 2,523,004 Fowler Sept. 19,1950 2,527,974 Tostenrud et a1 Oct. 31, 1950 2,531,732 Hoffman Nov. 28, 1950 2,573,227 Sheeley Oct. 30, 1951 2,666,589 Danyluke Jan. 19, 1954 2,877,956 Sackett Mar. 17, 1959 FOREIGN PATENTS 66,580 Austria Sept. 11, 1914 

